1. Field of the Invention
The present invention relates to a data transfer system that transmits data in a plurality of formats via a plurality of channels and, more particularly, to electronic apparatuses constituting nodes of the data transfer system and a channel assignment method for use in the data transfer system.
2. Description of the Related Art
A conventional data transfer system is constituted by electronic apparatuses interconnected by different kinds of cables corresponding to different data formats or protocols. Such a system is referred to as a physically constituted system. Another conventional data transfer system is constituted by electronic apparatuses interconnected by a common cable for transmitting data in a plurality of data formats. Such a system is referred to as a logically constituted system. For example, the latter system can be built up based on a standard known as IEEE1394.
The physically constituted system requires special cables designed for different data formats used in the data communication. The system involves drawbacks such as taking time for physical connection of different cables, creating considerable administration cost, giving clumsiness in external appearance, and causing connection error or confusion.
The logically constituted system can interconnect the participant electronic apparatuses with a single type of the common cable, involving no problem that may otherwise be caused by the presence of many cables of different types. This system also facilitates broadcast or multicast processing in which same data is transmitted to a plurality of destinations.
In the physically constituted system, the different types of cables must be provided for all different data formats used in the data communication as described above, so that the data flow among the participant electronic apparatuses can be visually recognized with respect to each protocol adopted between a pair of source node and a destination node.
On the other hand, in the logically constituted system, the data flow among the participant electronic apparatuses is controlled by software or computer program, making it substantially impossible to visually grasp the data flow or routing. That is, simply interconnecting the participant electronic apparatuses or components with the common cable of a single type cannot in general ensure the desired routing. Thus, although the logically constituted system has many advantages, the difficulty in the visual checking of the routing and connection states may hinder desired operation of the system such as musical tone generation and image reproduction. The conventional system may fail to operate properly when the system is set up by interconnecting components or nodes. The difficulty in the visual checking of the routing also makes it difficult to troubleshoot communication failure, hindering ease-of-use of the data transfer system or network system.